FIG. 8.

Altered MAP kinase activation is restored by treatment with cyclosporine A. Control cells (Jk) and cells expressing HCV C (JHC.d, JHC.g, and JHC.h) were stimulated with TPA and an anti-CD28 antibody (α-CD28) for 20 min. Where indicated, the cells had been pretreated with cyclosporine A (CsA; 50 ng/ml) or cultured in calcium-free medium (−Ca²⁺) for 24 h. Phosphorylated forms of ERK1/2 (A), p38 (B), and JNK1/2 (C) in cellular extracts were detected by Western blotting as described in the legend to Fig. 6. The positions of molecular size markers (in kilodaltons) are shown to the right. The data presented are representative of three independent experiments.